Purpose: This cross-sectional study aims to evaluate saliva, serum levels of interleukin-21 (IL-21), IL-33, and
prosta glandin E2 (PGE2) in patients with generalised chronic periodontitis or aggressive periodontitis.
Materials and Methods: Before initiation of any periodontal treatment, saliva and serum samples were collected
and clinical periodontal measurements were recorded from 94 participants (25 aggressive periodontitis patients,
25 chronic periodontitis patients, 44 periodontally healthy individuals). IL-21, IL-33 and PGE2 levels in serum and
saliva samples were determined by ELISA. Data were tested statistically using Kruskal-Wallis, Mann-Whitney U-,
and Spearman-rho rank tests.
Results: Saliva IL-33 levels were statistically significantly higher in the chronic than the aggressive group (p < 0.05).
Serum IL-33, saliva and serum IL-21 and PGE2 levels were similar in the two periodontitis groups. Saliva IL-33 levels
correlated with age in the chronic periodontitis group (p < 0.05). Statistically significant positive correlations
were found between serum, saliva PGE2 levels and plaque index (p < 0.05). IL-33 and IL-21 levels in serum samples
positively correlated in the periodontitis groups (p < 0.05).
Conclusion: IL-21 and PGE2 analysis did not exhibit discriminating data between generalised chronic and aggressive
periodontitis, but the present findings support the role of these cytokines in periodontitis. Statistically significantly
higher saliva IL-33 levels in the chronic periodontitis group warrant further research.